Distillation of tar, etc.



Aug. 1, 1933. s. P. MILLER 1,920,801

DISTILLATION 0F TAR, ETC

Original Filed Dec. 51, 1926 5 Sheets-Sheet l INVENTOR WMWM . 4 7,2;{SM/MM; Y

ATTORN EYS mg. 1, 1933. s. P. MILLER 1,920,801

DISTILLATION 0F TAR, ETC

Original Filed Dec. 31, 1926 5 Sheets-Sheet 2 ATTORN EYS 19330 s. P.MXLLER Y 13263801 DISTILLATION 0F TAR, ETC

Original Filed Dec. 31, 1926 5 Sheets-Sheet 3 INVER WWW ATTO R N EYSAug. 1, 1933.

S. P. MILLER DISTILLATION OF TAR, ETC

Original Filed Dec. 31, 1926 5 Sheets-Sheet 4 INVENTOR 4 7%; 3MAW1; v6

ATTORN EYS 1933. s. P. MILLER- DI'lILLATION OF TAR, ETC

Ofiginal Filed Dec. a1, 1926 5 Sheets-Sheet s INVENTOR WZ m l; m,m

ATTORN EYS Patented Aug. 1, 1933 UNITED STATES PATENT OFFICEDISTILLATION 0F TAR, ETC.

Stuart Parmelee Miller, Englewood, 'N. J., as-

signor to The Barrett Company, New York, N. Y., a Corporation of NewJersey 8 Claims. (Cl. 202-84) This invention relates to improvedapparatus for the distillation of tars and the production of pitches anddistillate oils therefrom at coal distillation plants, such asby-product coke oven plants.

In the ordinary operation of by-product coke ovens the gases produced bythe coking operation pass from the individual ovens through individualuptake pipes and goose-necks to a collector main or mains common to abattery of ovens. The coke oven gases leaving the ovens at a hightemperature are cooled to separate tar constituents therefrom, the tarconstituents being separated partly in the collector mains and partly insubsequent condensers.

Coal tar produced at by-product coke ovens is commonly shipped orconveyed to tar distillation plants where it is subjected todistillation for the recovery of coal tar distillates and the productionof pitches as residues of the distillation.

The present invention provides improved apparatus for tar distillationin which the tar is distilled directly at the by-product coke ovenplants without the need of a separate tar distillation plant and withouttransportation expense, and with the production from the tar ofdistilled oils and of pitches as residues of the distillation.

According to the present invention, the hot coke oven gases, as theycome from one or more of the individual coke ovens, are utilized for thedistillation of tar and the separation of vaporizable oils therefromwhich are separately recov-- ered, and the production of pitches, bybringing the tar into intimate contact with the hot .coke oven gasesimmediatelyv after they leave such coke ovens, or at least while theyare at a temperature high enough to accomplish the desired distillation.I

The distillation of the tar carried out with separate condensation andrecovery of the distilled oils, admixed with only such oil and tarconstituents as are contained in or remain in the coke oven gas employedfor the distillation.

According to the present invention, the tar to be distilled is sprayedor otherwise brought directly into contact with the hot coke oven gasesfrom a limited number of individual ovens, at a sufficiently hightemperature so that the tar is ciiectively distilled thereby, withseparation therefrom of a greater or less amount of volatile oils,leaving 'a heavier tar or pitch as the residuum product of thedistillation, and the gases and admixed vapors from the distillation arekept separate from the coke oven gases from the other ovens; Thespraying of the tar into the a single coke oven produces, so that thetar from hot coke oven gases results in partial cooling of these gasesand separation therefrom of more or less of the heavier tarconstituents, a proportion of which are thus thrown down and added tothe pitch residue from the tar distillation. This distillation of thetar also results in an increase of condensable vapors in the hot cokeoven gases treated as well as in the partial or preliminary removal fromthe gases of heavier tar constituents, so that these coke oven gases intheir partially purified condition and with the increased amount ofvapors from the distillation of the tar, differ in composition from theordinary coke oven gases not so treated.

In the practice of the invention, the tar to be distilled is sprayed oratomized into the hot coke oven gases, or is otherwise brought directlyinto intimate contact therewith, so that the hot gases can heat anddistill the tar and carry off the distillate vapors, and these vaporsare then separately condensed, together with vapors which the gasesthemselves contain.

Certain of the individual coke ovens, according to the presentinvention, are provided with a gas collecting system or systems of aconstruction which will enable the tar to be sprayed or otherwiseintroduced directly into a stream of the hot coke oven gas immediatelyafter it leaves the coke oven, or before the temperature has beengreatly reduced. Such gas collecting system or systems mayadvantageously be uptake stills in the form of modified uptake pipes,such as hereinafter described, in which the tar is sprayed or atomizedinto the stream of the hot coke oven gas while the gas is atsubstantially its maximum temperature, but the invention in its broaderaspects is not limited to the use of such uptake stills. Other apparatusmay be employed to utilize the hot gases for the direct distillation-oftar.

The distilling capacity of the gases from a single coke oven is greatlyin excess of that required for distillation of the amount of tar which aconsiderable number of coke ovens can be distilled in a single uptakepipe by the hot gases from a single oven.

In the construction of a battery of ovens, for distilling all the tarproduced on the battery, it is therefore sufficient to provide a fewonly of the individual ovens with uptake pipe stills for distilling tarwith the hot coke oven gases, and the remainder of the coke ovens of thebattery may be operated in the ordinary way, the recovery of coal tarfrom their gases being accomplished in the ordinary manner. Suchrecovered coal tar may then be distilled in the few uptake pipe stillsto produce pitches therefrom'and to permit recovery of the vaporizedoils from the distilled tar, together with tar and oils normally presentin the gases.

I For the most part, the construction of the coke oven battery and ofits by-product recovery system may remain unchanged, so that the greaterproportion of the coke ovens may be or remain of usual construction, andthe gases therefrom may be collected in the usual collector main, andthe tar separated therefrom in the usual way.

A part only of the coke oven battery will be changed by the provision ofthe uptake stills arranged for the distillation of tar by the hot cokeoven gases and for the production of distillate and pitch therefrom.This part of the battery, provided with such modified construction ofthe gas outlet pipes, has its own collecting, cooling and condensingsystem so that the coke oven gases employed for and mixed with thevapors produced from the distillation of the tar, can be cooled for theseparation of tar and oil constituents therefrom independently of themain gas collecting, cooling'and recovery system of the battery.

It is one advantage of the present invention that it can be directlyapplied to existing or present day coke oven production. Present daycoke oven operation so far as the production of coke is concerned, isunaffected, while nevertheless tar may be distilled and pitch producedand oils recovered in the separate gas collecting and condensing system.This special distilling and condensing system does not interfere withthe operation of the coke ovens. The by-product recovery system for thecoke ovens which are not modified by the provision of the uptake pipestill can be operated in the ordinary way.

Another important advantage of the present invention is that theemployment of a separate collector main, with separate cooling andcondensing system insures an easier control of the temperature of thedistillation process than would be possible with the use of the uptakepipe stills leading to the collector main for the other ovens of thebattery. In other words, the volume of tar required to produce arelatively large change in the temperature of the gases in the separatecollector main and in the separate uptake stills would have relativelylittle efiect upon the temperature of the total volume of gases evolvedby the whole battery. Proper temperature control is important, when taris introduced into the gases, because maintenance of the apparatus ingood condition is attained thereby and in addition products producibleat definite temperature ranges may be secured with certainty.

The tar which is distilled according to the present invention may be tarproduced at the same coke oven plant at which it is distilled, or it maybe tar from another coke oven or other plant. The tar may be a heavytar, light tar, or heavy or light tar constituents which it is desiredto distill in order to separate distillate oils therefrom. Other tar,such as gas house tar, vertical retort tar or water gas tar, etc., canalso be distilled. Where blended or'composite pitches are desired, orcomposite or blended distillates, two or more different kinds of tar maybe separately distilled at the coke oven plant, or may be admixed insuitable proportions and be distilled together, giving directly acomposite pitch product. Where different tars are distilled, theresulting pitches may be blended to give a composite product, and thedistillates may like-' wise be blended when desired.

The amount of condensable oil vapors distilled from the tar in thepresent process may be in some cases less than the condensable oil vaporcontent of the coke oven gases employed for the distillation,particularly where the amount of tar distilled is regulated to secure arelatively high melting point pitch as a product of the process, andwhere only a limited amount of tar is subjected to distillation. Inother cases however, the vapors from the tar distillation maybeconsiderably in excess of those normally contained in the coke ovengases, so that these gases may be doubled or more than doubled in theirvapor content, giving a high concentration of condensable vapors in thegases. Moreover, the effect of the distillation is proportionately toincrease the content of relatively lighter oil vapors and to decreaseproportionately the content of heavy pitch constituents, owing to thepurifying effect of the tar spray in separating and throwing down someof the heavier constituents of the gases.

Where a few only of the coke ovens of a battery are employed for thedistillation of tar and separate collection of oil, in accordance withthe present invention, the separate condensing system or systems for thevapors from the coal gases of such ovens can be much smaller than themain condensing system for the remainder of the battery. Such separatecondensing system or systems may be of similar construction andoperation as the ordinary condensing system, from the standpoint of oilrecovery, or of diiferent construction and operation. Owing to theincreased condensable oil vapor content of the gases, a proportionatelysmaller amount of gases require handling, while, from correspondingquantities of the gases, a much greater amount of condensableconstituents can be recovered than from ordinary coke oven gases.

The manner in which the tar is brought into direct contact with the hotvapors can be varied. A suitable atomizing or spray nozzle, to which thepreheated and thinly fluid tar is supplied under a sufiicient pressureto bring about atom- 125 izing or spraying and resulting intimatecontact of the tar with the hot gases, can be located in the upper partof the modified uptake pipe to bring the tar into intimate contact withthe hot gases.

A single tar spray can be used in each of the individual uptake pipes,or a plurality or series of such sprays, and the rate at which the taris sprayed, as well as its temperature, can be regulated and controlledto obtain a greater or less degree of distillation of the tar and theproduction of distillates of desired characteristics, and of harder orsofter pitches or pitch-like products.

The gases escaping from the top of a coke oven are at a hightemperature, e. g., around 600 to 700 C., or in some cases much higher.The temperature of these gases is sufliciently high so that efiectivedistillation of the tar can be accomplished by an intimateand regulatedspray of the tar into the hot gases. By employing the gases atpractically top-of-oven temperature their maximum heating and distillingeffect is utilized. The amount of tar and the intimacy and time ofcontact of the particles of the tar spray with the gases, and the natureand. amount of oil distilled therefrom, can be varied. Efl'ectivedistillation can be accomplished with a temperature drop of the gaseswhile passing through the tar spray, of, for example, 100 0., althoughwith increased amount of tar or increased intimacy and time of contact agreater drop in temperature and increased distillation of oil canbeobtained. c

The tar in turn will be heated by the hot gases and the temperature ofthe tar will be very considerably raised. Part of the heat of the gases,however, is employed in vaporizing liquid constituents of the tarwithout corresponding increase in temperature of the tar, so that themaximum temperature of the tar and of the resulting pitch may beconsiderably below that of the gases.

In carrying out the process, the tar may be brought into contact withthe hot gases once only or it may be recirculated and again brought intocontact with the hot coke oven gases to bring about further distillationand the production of harder pitches, or even pitches of modifledcharacter, such as pitches of increased carbon content. This furtherdistillation may take place by recirculating the tar or pitch throughthe same distillation system, or through another or othersystems, sothat distillates and pitch of the same or similar character are producedin the different systems, or distillates and pitches of difierentcharacter in the difierent systems. By regulation of the rate and typeof tar spray and its temperature of preheating, and by redistillationwhen necessary, it is possible to regulate the hardness of the pitchesproduced, and produce softer or harder pitches, as desired, and

, oils of different characteristics may be formed.

The further distillation of, the pitch first produced in order torecover additional oil there-.

from, can be carried out in the same uptake pipe still, or it may besubjected to further distillation in another uptake pipe still. Byoperating separate uptake pipe stills as separate systems, it ispossible to produce distillates and pitch of diiierent characteristicssimultaneously, while by operating separate condensing systems with suchseparate distillation systems, condensed products of diiierentproperties can be simultaneously produced.

In a coke oven plant having a small battery of ovens, for example, atwenty oven battery, one or two uptake stills may be suflicient todistill the tar from the remaining ovens of the battery and such stillor stills may have a separate condensing system. In a larger coke ovenplant having a large number of ovens in the same or separate batteries,a larger number of the uptake stills will be required to distill the tarproduced by the remaining ovens of the battery or batteries. If tar froman outside source is distilled, a larger number of uptake stills maysimilarly be required. When a coke oven plant has several batteries ofovens, one or more uptake stills may be provided on each battery, or asuflicient number may be provided on a-single battery to distill the tarproduced by the other batteries and by the other ovens of the samebattery, to yield the desired quantities and qualities of distillates orof pitches.

Where several uptake pipe stills are provided for the distillation of alarge amount of tar, all of the uptake stills may be connected to thesame condensing system, or two or more separate condensing systems maybe provided. L Where two or more of the uptake stills are combined withthe same condensing system, these uptake stills may advantageously havea separate collector main for collecting the gases from the .uptakestills so that they. may pass through the separate condensing system.Where several uptake stills are provided, they may all be connected tothe same collector main a-nd the same condensing system, I

or different uptake pipes, or diiferent groups of uptake'pipes, may beconnected to separate collector mains, each having its own independentcondensing system, or the condensing systems can' be inter-connected.

In the operation of such separate collector main, the gases collectingtherein after passing thru the uptake still or stills may be cooled to arelatively low temperature, for example, by spraying with ammonialiquor, and a considerable amount oi' the condensable constituents canbe separated from the gases in the separate collector main or mains.Where it is desirable to throw a larger amount of the condensableconstituents over into the condensing system beyond the separatecollector mains or main, the temperature in such main or mains isadvantageously kept high, for example, by spraying tar in regulatedamount into the separate collector main or mains, or by spraying heavyoil such as anthracene oil, etc., into the collector main in regulatedamount and with regulation of the temperature so that the gases are notcooled to such an extent that too large an amount of the condensableconstituents are separated in the collector main. Tar which is thussprayed into the collector main may be dehydrated and recovered from themainalong with condensed constituents from the gases as a dehydrated andpartially distilled tar product. The gases, even after passing throughthe uptake stills will be at a sum-- ciently high temperature to effectdistillation of tar brought into contact therewith, as by spraying itintimately into the gases in the separate collector main. In such case,the hot coke oven gases will be employed in a two-stage distillation,first in the uptake still and second in the collector main. The tarwhich is dehydrated, or preheated, or both, in the collector main, maythen be conveyed to one of the uptake stills to effect its furtherdistillation and to produce pitch therefrom.

The gases after passing through the separate collector main then pass tothe condensing system in which further condensation of condensableconstituents takes place. Such condensation may be a fractionalcondensation in direct or indirect type coolers or condensers of thetype now commonly employed for recovering condensable constituents fromcoke oven gases, or the gases may be subjected to fractionalcondensation in a stage-by-stage scrubbing system, as, for example, byscrubbing them with oils at progressively lower temperatures.

In systems where different uptake pipe stills, or different groups ofuptake pipe stills, are connected to separate condensing systems, eachsystem may, if desired, operate upon a different material; for example,one system may distill tar in the manner described, and another systemmay distill a mixture of oils for the separation of different oilconstituents therefrom.

It is one advantage of the improved apparatus of the present inventionthat it makes possible the keeping of the distilled oils separate fromthe main condensing system of the coke oven battery, so that, whateveroils or tar constituents are distilled in the uptake stills, they can beseparately tion and condensing systems, different products can besimultaneously distilled. A migzture of" oils having a wide boilingpoint range can'be' subjected to "distillation in one of the uptakestills, or' in a group of uptake stills, having a separate condensingsystem, and the mixture thereby fractionated, giving the heaviestfraction as products from the uptake stills, admixed with such tarconstituents as are separated from the coke oven gases in the uptakestill, while the other oil constituents can be recovered partly in theseparate collector main-or'mains, and partly in the subsequentfractional condensers o coolers.

The present invention is thus of more or less general application to thedistillation of tar and oils and the recovery of distillates. Itprovides for the distillation of tars and oils by means of the heat 'ofthe hot coke oven gases, with provision for separately condensing theresulting distillate or distillates fractionally or otherwise. Theinvention also includes coke oven batteries or coke oven plants equippedfor balanced operation in the sense that a part of the coke ovens areprovided with uptake stills for the distillation of tar provided by theremainder of the battery or batteries in such cases as it is desired todistill part or all of the tar from the remainder of the battery at thesame coke oven plant and produce distillate and pitch therefrom.

The invention will be further illustrated by the following more detaileddescription taken together with the accompanying drawings, which showapparatus embodying the invention, but it is intended and will beunderstood that the invention is illustrated thereby but not limitedthereto.

In the accompanying drawings Fig. l is a view in elevation with part insection showing a portion of a coke oven provided with an uptake pipestill and separate collector main;

Fig. 2 shows a plan view of a part of a battery of coke ovens with partof the ovens provided with the uptake pipe stills and with a separatecondensing system;

Fig. 3 is an elevation taken at right angles to Fig. 2, showing theseparate condensing system and a part of one of the coke ovens withuptake pipe still;

Fig. 4 shows a modification of the apparatus of Fig. 1: I

Fig. 5 is an enlarged view of one form of the modified uptake pipe;

Fig. 6 is a sectional view taken on the line 6-6 of Fig. 5;

Fig. 7 is a sectional view taken on the line 7-7 of Fig. 5; and

Fig. 8 is a sectional view showing one of spray nozzle.

The invention is of more orless general application to different typesand constructions of by-product coke ovens such as Semet-Solvay ovens,Koppers ovens, etc., but will be more particularly described andillustrated in connection form with by-product coke ovens of theSemet-Solvay type.

In Fig. 1 is illustrated one of the coke ovens of a battery, with gaspiping modified to provide for the distillation of tar or oils with thehot coke oven gases which rise from the oven. The coke oven isillustrated conventionally at l and has the usual gas outlet 2 for theescape of the hot coke oven gases. The uptake pipe still, viz.,

w: recovered; while by operating diiferent distillathe modified uptakepipe, may consist generally of the outlet pipe "3, the' casing 4and theuptake L 5; 'The outlet pipe 3 is seated in'a suitable seal over the gasoutlet 2 and connects at its upper end with thelower end of the casing4.

The upper end of the casing 4 connects with'the uptake L 5which-leads-to a' main 6' which may be similar to the ordinary collectormain but smaller in size. The casing 4 is enlarged to provide a spacearound the inner pipe 7 which extends upwardly into the said enlargedcasing. The lower ends of the pipe 7 and the casing 4 are preferablyintegral or threaded one within the other or joined by means of a collarsuitable -to provide an annular receptacle between the pipe 7 and casing4.

Located within the casing and above the end of the pipe 7 is a baflie orhood 8 and above this in the -upper part of the casing 4, or in the pipe5 above the casing, is arranged the spray-head 9 connected with a pipe10 for supplying tar or oil thereto. An outlet 11 for pitch or residueis located at the bottom of the enlarged casing 4 for discharging pitchor residue from the annular space between the pipe '7 and thesurrounding casing 4. The casing 4 is attached by means of flanges 12 atthe lower end to the outlet pipe 3 which in turn is sealed in the roofstructure of the oven to take the gases rising through gas outlet 2 fromthe oven chamber. At its upper end the casing 4 is connected by flanges13 with uptake L 5 which in turn connects through the valve box castingwith collector main 6.

The casing 4 illustrated in Fig. 5 has a series of doors or openings 14near the bottom to permit inspection and cleaning and has an upper door15 ca y g the baflie or hood 8, the arrangement being such that when thedoor 15 is opened the baflie 8 is removed from the casing 4. The casingis also provided with overflow outlets 16 located some distance fromthebottom of the annular space therein. The pitch or residue outlet 11 nearthe bottom of the casing 4 is connected by means of a pipe 18 to a pitchreceptacle 19.

The connection from the uptake pipe still to the collector main may beprovided with a spray 20 for cooling and assisting in condensing thecondensable constituents of the gas and additional spray nozzles 21 mayalso be provided in the small collector main, although these may beomitted where sudden cooling of the gases is not desired. Ammonia liquorcan be used in such sprays or tar or a mixture of liquor and tar. Someheavy tar constituents may be carried along with the gases and separatedor condensed after leaving the uptake L 5 although the amount of heavytar and pitch constituents may be proportionally much less thanseparated from ordinary coke oven gas, owing to the purifying efiect ofthe tar spray in the uptake pipe still in removing part of the heaviertar and pitch constituents. The condensable oil vapor content of thegases, moreover, will be much higher than in ordinary coke oven gases sothat upon cooling the gases for the separation of oils therefrom, aproportionally much greater amount of oils will be obtained than ofheavy tar or pitch con stituents. By fractionally cooling and condensingthe vapors from the gas, different fractions can be obtained, part ofwhich may be relatively clean oil. When substantially all of the oilvapor constituents are condensed together, the product may be a tarryoil but with only a relatively small amount of heavy tar constituents,

as mentioned above.

tion and the others provided with uptake pipes 29 of ordinaryconstruction. The usual collector main connects with the uptake pipes 29and with the cross-over main 30 leading to the c'oolers or condensers 31and 32, connected to decanter 34. The exhauster for drawing the gasesthrough the system is indicated at 35.

This part 01' the system of Fig. 2 is a common type of by-product cokeoven system. The tar collected in the collector main and cross-over mainis shown as running to a tar collecting tank or decanter 23 in which thetar separates from the ammonia liquor and this tar in turn is shown asleading to a dehydrator 24 for partly or completely freeing the tar fromwater and preheating it for distillation. The dehydrator may be of anysuitable construction. The dehydrated and preheated tar is then pumpedby the pump 25 through the tar supply pipe 10 to the spray nozzles 9.

The condensing and recovery system connected to the uptake pipe stillsis shown by way of example as similar to that of the main recoverysystem but smaller in size. From the small collector main 6 the gasespass through a pipe corresponding to a cross-over main 30a to condensers31a and 32a and then to the same exhauster 35 which may be common toboth condensing systems, or separate exhausters (not shown) may beemployed. Any tar or oily tar or tarry oil separating in the smallcollector main, as where ammonia liquor spray is employed therein, maybe run to the receptacle 33a. for the separation of ammonia liquor fromthe oil or tar. If this tar is a heavy tar, in case the heavier tarconstituents are condensed without any considerable admixture of oils,this heavier condensate may be returned for further redistillation torecover pitch therefrom, and to throw the oils back into the system sothat they can be subsequently condensed in a more or less purifiedstate. The tar or oil separated from the small collector main,particularly where it contains a large amount of heavy oil, may bedirectly utilizable, alone or in admixture with other materials, forexample, as creosoting or other material, while the oils separated inthe condensers can also be directly utilized, and maybe relatively cleanoil.

In the apparatus illustrated in Fig. 2, a common tar supply is shownleading to the uptake pipe stills, and all of these uptake pipe stillsare distillation in all of the uptake pipe stills will be collectedtogether.

In some cases, however, it may be advantageous to operate one or more ofthe uptake pipe stills in a different manner from that in which theothers are operated. For example, tar which has been distilled in oneuptake pipe can be redistillable in another uptake pipe still to drive011 an additional amount of heavier oil vapors therefrom and give aheavier pitch. In such cases, separate collecting and condensing systemscan be provided for the individual uptake pipe stills so that heavieroils can be recovered from one than from another. Thus, for example,uptake pipe stills 5b may be connected to two of the ovens and to asmall collector main 6b. Tar or oil to be distilled may be fed to thestills through spray nozzles 9b and the distillation may be conducted asin the stills 5. The pitch produced in the stills will be withdrawnthrough a pipe 11b and the gases carrying the distilled vapors will bewithdrawn through a cross-over main 30b and delivered to condensers 31band 32b to which decanters 34b are connected. A decanter 33b permitsseparation of the condenser oils from the ammonia liquor which separatesin the crossover main. The condenser 32b may be connected to theexhauster 35 to facilitate the flow of gases and vapors through thesystem.

In Fig. 4 an arrangement is shown for recirculating the pitch producedfrom one distillation so that it may be redistilled in a seconddistillation, and the coke oven gases employed in said respectivedistillation, with difierent oil vapor content, can be separatelycollected and condensed in separate condensing systems. In this way, afractional distillation of the tar can be effected, taking off first themore volatile constituents and giving a soft pitch, then redistillingthe soft pitch to take oif heavier constituents and give a harder pitch,and the lighter and heavier oils driven off by these successivedistillations can be separately condensed along with the vapors of thecoke oven gases by which they are carried. In Fig. 4 the pitchreceptacle 19 is shown as having a pipe 27 leading therefrom to thespray nozzle and a pump 26 in this line for recirculating the pitch ortar.

One suitable form of spray nozzle is indicated in Fig. 8, this having anouter casing 36 with an inner core 37 having helical passages formedbetween it and the outer casing 36 and with the nozzle orifice 38. Theconstruction is such that the tar or oil is discharged with a whirlingmotion in the form of a conical spray. The tar or oil, when it ispreheated and thinly fluid, may be pumped to the nozzle under a suitablepressure, for example, 40 pounds per square inch and discharged throughthe nozzle so as to atomize or spray it into the hot uprising gas.

In the operation of the apparatus illustrated, the hot gases from thedistillation of coal in the coke oven pass upwardly through the uptakepipe stills and thence through the connecting piping to the condensingsystem which in the apparatus illustrated is in part a small collectormain. The remainder of the battery of ovens can be operated in theordinary way to separate tar fractionally or completely from the cokeoven gases, as by spraying ammonia liquor or tar or both into thecollector main and separating out more or less of the tar in thecollector main and then passing the gases through coolers or condenserswhere the remainder of the tar or oily constituents is for the most partseparated. The entire tar or oil,

separated both in the collector main and in thesubsequent coolers orcondensers, may be admixed and employed for redistillation. or only theheavier tar may be so distilled or only the lighter tar or oils may beused or tar or oils from another battery of ovens or from anotherplantmay be employed in the process. The distilling capacity of the hot cokeoven gases is so greatly in excess of the amount of tar or oils which isnormally producedfrom the gases that a few only of the ovens, whenprovided with the new uptake pipe stills, can distill the tar or oilsproduced by the rest of the battery, and a larger number of ovens can beemployed to distill tar or oils from other batteries or from otherplants.

The tar or oil to be distilled is supplied in regulated amounts to thespray nozzle and sprayed into the hot coal distillation gases. The taror oil may be advantageously preheated before bein so sprayed. The hotcoal distillation gases are brought into intimate contact with the sprayof taroroilaudthetaroroilisheatedanddistilled by the hot gases, whilethe hot gases themselves are somewhat cooled. The tar or oil isprevented from falling down into the coke ovens by the bailie 8 andcollects in the space outside the pipe 7 and runs out through the pitchor residue outlet 11. The action of the hot gases upon the particles oftar or oil spray or upon the tar or oil otherwise brought into intimatecontact with them and flowing down over the surfaces of the uptake pipestill, is such that the tar or oil is heated and volatile oils distilledtherefrom so that a heavier tar or pitch or residual oil collects andruns out through the pitch or residue outlet. The distillation can beregulated in the manner herelnbefore described, as by preheating the taror oil to a greater or less extent before spraying it into the hotgases, or by regulating the rate or character of spray, etc. The tar oroil may be subjected to a high temperature for only a short period oftime. As a result, a low carbon pitch, as compared with ordinarydistillation, can be directly produced without any appreciable increasein carbon content over that normally present in the tar from which thepitch is produced.

The gases after leaving the uptake pipe still and while still at arelatively high temperature may be further cooled, for example, byammoma liquor or tar sprays in the small collector main, before passingto the condensers, or the gases may be passed to the cross-over mainandto the condensers while still at a high temperature. Depending uponthe method of cooling and condensation, the oils from the redistillationof the coal tar, together with oil and tar constituents from the normalcoal distillation gases employed in the tar distillation, can beobtained in part in the collector main and in part in the subsequentcoolers or condensers as relatively clean oils or tarry oils or oily tarcontaining a greatly decreased content of heavy tar constituents andmade up mainly of oils.

When tar or oils are sprayed into the gases in the separate collectormain, the heat of the gases will effect partial distillation thereof,and such sprays will fm-ther cool and clean the gases, re-

moving some of the heavier tar constituents and.

increasing their content of oils. In such cases the hot coke oven gasesare employed twice, in series, at a higher and then at a somewhat lowertemperature, to distill tar or oils, and the gases so employed are twicescrubbed or cleaned by the tar or oil sprays. Where the residue from thesecond or subsequent treatment or treatments is used in the firsttreatment, the operation becomes countercurrent, and the tar or oils arepreheated (and may be dehydrated) as well as partly distilled, by thegases at the lower temperature before further distillation by the gasesat the higher temperature. Nevertheless the heat of the gases is suchthat eflective distillation of a large amount of tar or oil can be soeffected, while still leaving the gases at a high temperature such thatthey carry a large amount of condensable oil constituents recoverable inthe separate condensing system, fractionally or otherwise.

In the operation of the battery illustrated in Fig. 2, most of the ovensare provided with uptake pipes of usual construction which may haveammonia liquor or tar sprays in the goose-neck or uptake L and in thecollector main to separate a considerable amount of heavy tar in thecollector main and to give gases of low tar content going to the coolersor condensers. The an entire tar product, or only the heavier tar, oronly the lighter tar, can then be employed as the tar to be distilled,for example, by passing the vtar to a dehydrator and there dehydratingand preheating it and then bringing the preheated tar into-intimatecontact with the hot coal distillation gases from the coke ovens so asto utilize the high temperature and heat of these gases to distill thetar and produce distillates and pitch therefrom.

The part of the battery thus employed for tar distillation purposescombines in its, function that of a. coke oven plant for producing cokeand coal distillation gases, and the distillation of tar by the hot coaldistillation gases, thus combining a tar distillation plant with thecoke oven plant and eliminating expense of transportation of the coaltar from the coke oven plant to the tar distillation plant while alsogreatly reducing plant cost and fuel cost for the tar distillation byutilizing the hot coal distillation gases, the heat of which isvalueless and which must commonly be removed at large expense.

The uptake pipe and the circulating lines, etc., are illustrated in thedrawings in a conventional manner and without any insulation aroundthem, but where it is desired to prevent loss of heat by radiation, orto reduce such loss, or to prevent undue cooling of circulating lines,etc., such circulating lines, and the uptake pipesand connecting pipesthrough which the gases and liquids pass, can be provided with heatinsulation.

Furthermore, the hot coal distillation gases from the coke oven can becooled somewhat 5 before'bringing them into contact with the tarprovided their temperature is still sufliciently high to bring about thedesired distillation of the tar and the production of distillates andpitch therefrom. It is advantageous, however, to utilize the hot gasesat their maximum temperature, immediately after they escape from thecoke ovens, by employing them in the manner described.

While I have described and illustrated a particular type andconstruction of uptake pipe still, it will be evident that the inventionin its broader aspects can be carried out in apparatus of otherconstruction in which the tar or oils are distilled by the hot gases andthe distillates separately condensed in the manner described.

This application is a division of my co-pending application Serial No.158,137, filed December 31, 1926 which has matured into Patent No.1,844,889.

I claim:

1. A by-product coke oven battery which comprises means to remove tarfrom the gases from I the ovens of part of the battery thereby producinga cooled vapor-containing gas, means to bring tar into contact with hotgases evolved by ovens of another part of the battery before passingthem through cooling means and means to condense vapors obtained fromsuch contact separately from the vapors contained in said cooled gas.

2. A battery of coal distillation ovens or retorts having separatecondensing systems for coal tar constituents from ovens in difierentparts of the battery, and means for bringing tar into direct contactwith hot distillation gases from 150 at least one of the ovens orretorts of one of these parts of the battery before cooling them so asto effect distillation of the tar and the production of pitch therefrom,whereby the gases admixed with the vapors of one condensing system areenriched by the vapors from the distillation.

3. A by-product coke oven plant having one or more condensing systemsfor condensing coal tar constituents from a number of the ovens of theplant, at least one of the ovens of the plant being provided with meansfor bringing the tar into direct contact with the hot coke oven gases ata temperature sufficient to distill the tar and produce pitch therefrom,and a separate condensing system for the resulting admixed gases andvapors.

4. A by-product coke oven battery having most of the ovens connectedwith condensing systems for condensing tar constituents from the gases,a few of the ovens being provided with uptake pipe stills for distillingtar by bringing it into direct contact with the hot coke oven gases, anda separate condensing system for that part of the battery which includessuch uptake pipe stills.

5. A by-product coke oven battery having at least one collector mainconnected with the uptake pipes for most of the ovens of the battery andmeans for collecting tar from the coke oven gases, means for dehydratingthe tar, and means for bringing the dehydrated tar into direct contactwith hot coke oven gases from another part of the battery before coolingthem to eifect distillation of the tar, and a separate condensing systemfor the gases from that part of the battery where such distillationtakes place.

6. A by-product coke oven battery having a collector main connected withthe up-take pipes from most of the ovens of the battery, distillingmeans connected directly with a few of the ovens of the battery and twocondensers, one connected with the collector main and the otherconnected with the distilling means.

7. A by-product coke oven battery, which comprises means to remove tarfrom the gases from the ovens of part of the battery, means to bring tarinto contact with hot gases evolved by ovens of another part of thebattery before passing them through cooling means, a condenser, means topass the gases with which tar has been brought into contact to saidcondenser and means for passing both the gases from the condenser andthe first-mentioned gases after the removal of tar to the sameby-product recovery means for the removal of further by-products.

8. A by-product coke oven battery, which comprises means to remove tarfrom the gases from the ovens of part of the battery, means to collectthe tar thus removed, means to convey tar from this collecting means andbring it into contact with hot gases evolved by ovens of another part ofthe battery before passing them through cooling means, and cooling meansto which the resulting gases are passed, said cooling means beingseparate from the said means for removing tar from the gases.

STUART PARMELEE MJILER.

